Air compressor for woodturning

I just bought a DeWalt pancake compressor for woodturning. I’ve been working wood for 35 years but have never owned a compressor before. The manual says after each use to 1. ensure regulated pressure gauge reads 0 psi, 2. drain air tank, 3. drain water by opening drain valve.

I’ve been forgetting to do all this every evening before turning in. Question: do I need to follow these procedures faithfully?

18 replies so far

My compressor is left plugged in, pumped up, and in the ‘on’ position 24/7, and I drain the tank roughly once a year if I can remember :) YMMV. But I have to ask, how do you use a compressor for woodturning?

Hi Brad – the compressor is useful for blowing out shavings when hollowing small Christmas ornaments.

Got it… not so much for woodturning but for clean up :) Yup, they are useful for that for sure.

Cheers,Brad

PS: I’ve found using a shop vac works better for cleaning up around my lathes and turning projects (particularly for bowls) as it doesn’t scatter the wood chips all over the place. Even more so for my metal turning lathes.

Air compressors will collect water during regular use, in damp climates they collect more. Some shopsuse air driers to remove moisture. If too much moisture collects in the tank, it will spray out along withthe air you are using. I put an elbow on the bottom of my compressor and ran a length of pipe to theside with a ball valve on the end, I just open the ball valve and let the water drain out under pressureabout once a week.

I know my air compressor has been drained at least once this year because I moved it. But for the most part, I’m much closer to MrUnix than what the manual recommends in terms of how often I shut it down and drained it. In my old shop, I would do it more often since the compressor (I use a Makita MAC2400) was out in the open and easy for me to get to. Now, in my new house, it is in the back of a closet next to the dust collector unit and it is a pain in the butt to get to the release valve.

Back when I worked at the big orange box, we had an air compressor in the tool rental dept (where I worked) it was under a work table and had a bunch of “stuff” piled on top of it. One day, it started to sound like it was “dragging” as if someone was holding the pulley so it could barely turn. I asked the dept manager how long had it been since we had serviced it? He couldn’t remember the last time it had been.

So I dragged it out and checked the oil in the motor… looked kinda dark but was still viscous enough. Pulled the air blow-off valve to run out any air in the tank and water started blowing out! So I took it outside and tipped it up and first thing I noticed was it did NOT have a water drain valve on it. Also when I tipped it up I was surprised at how HEAVY it was. I could feel the water inside the tank was sloshing around.

I then pulled the drain plug from the bottom …. by the time the water stopped running, I knew what was wrong. The tank was absolutely FULL of water. I got it drained and cleaned the whole thing up and installed a drain valve. It ran fine after that.

So yeah, air compressor are VERY useful in the shop, but you shouldn’t have to drain the air and water every day. It should have a water drain valve and you can check it about once a week. Mine here in my shop has an automatic water valve and it does what it’s supposed to.

I believe one claim is that these compressors can rust out from the inside, leading to a tank integrity failure, if you don’t remove the water from them periodically. That’s the claim anyway. I don’t know how likely that really is. You would think that higher-quality tanks are lined in some way, but I don’t really know.

I’m inclined to think that the manufacturer’s recommendation to bleed the air/water with every use is a bit of overkill, and primarily CYA. It’s not that there’s anything wrong with it, but it’s also more frequent than is really needed. If you did it once a month, that would probably be more than the vast majority of compressor owners. If you did it once a week, I would consider you very diligent. Generally, the more the compressor runs, and the more humid it is at the time it’s running, the more important it is, and vice-versa. If you’re going away for a few days, it wouldn’t hurt to leave it drained and turned off to avoid unnecessary cycling.

I’m thinking it’s less of an issue with a smaller compressor because it won’t take too long to refill the tank. My 33 gal tank takes forever.

Compressors used for house framing can gather a pint of water per 8 to 10hr day. Not only does the air condensate to water but it also drags all the oils and pollen in the air, if the discharge is creamy colored that’s from the oils and pollen. Maintaining an indefinite tank pressure just adds more stress to a non industrial tool not meant to do that, it’s meant to cycle.

If you value the tool follow the maintenance instructions, then if something fails like seals and gauges before the warranty ends you can justifiably request replacement.

The more humid your environment, the more often you have to drain the tank. Here in Georgia, I have electric water condensation drains at each tank, and two more on the inlet and outlet of the refrigerant drier for the system.Piston compressors are notorious for pumping lots of water into systems. Anyone with a spray booth or CNC router will want both a condensate drain and a dryer in their air system.

If you really want to make sure your air is dry, then install condensate drain that you can set duration and interval values on. You could also get a dessicant dryer if you install airlines in your shop.

But you really need to keep tabs on the water regardless. It can build up pretty quickly. And if your tank burst because of rust, it can be quite violent and dangerous.

With a little pancake compressor it’s not going to be the same as industrial size compressors, but the principal is still the same. Gotta drain that condensate.

I believe one claim is that these compressors can rust out from the inside, leading to a tank integrity failure, if you don t remove the water from them periodically. That s the claim anyway. I don t know how likely that really is. You would think that higher-quality tanks are lined in some way, but I don t really know.

- jfoobar

Definitely a realistic possibility—I read a report years ago written by a woodworker who had his compressor blow up due to rusting from the inside (a pancake model, if I recall correctly). Yes, the odds are probably low, but considering how much it cost him to replace the part of the wall that blew out, and some other casualties, I find myself draining my Porter Cable pretty often.

-- My mother said that anyone learning to cook needed a large dog to eat the mistakes. As a sculptor of wood I have always tried to keep a fireplace. (Norman Ridenour)

Definitely a realistic possibility—I read a report years ago written by a woodworker who had his compressor blow up due to rusting from the inside (a pancake model, if I recall correctly). Yes, the odds are probably low, but considering how much it cost him to replace the part of the wall that blew out, and some other casualties, I find myself draining my Porter Cable pretty often.

With one of those inexpensive pancake compressors, I certainly believe it. Many of them are under $100 for a reason, including the likely use of inexpensive materials to build them. I am not trashing them, mind you. If all one needs is to run an airhose for blowing dust away or filling the occasional bike tire, why buy more. I only bought my slightly larger Makita so that I could run some additional air tools and because it is quieter. 98% of my compressor usage is blowing dust away.